How to Measure Inseam (and What It Means)

Your inseam is the length of the inside leg seam, from the crotch seam to the bottom of the hem. To measure it, lay a pair of trousers whose length you like flat on a table, fold one leg out of the way, and run a soft tape from the point where the crotch seams meet straight down to the hem. That number, in inches, is the second number on a pair of jeans: a 32 x 30 has a 30 inch (76 cm) inseam.

What does inseam mean?

Inseam is one of three length measurements on trousers, and they are easy to mix up.

The inseam is the one to remember. As Gentleman's Gazette puts it in How Pants Should Fit, the outseam depends on the rise, but the inseam stays the same. A high-rise and a low-rise pair can both have a 30 inch inseam and differ by several centimeters on the outside.

Three ways to measure your inseam

Method 1: Measure trousers that fit (most reliable)

This is the method Proper Cloth and Lands' End give their customers, and it gives the number you actually buy, because it already includes the shoe and the break you like.

1. Pick trousers of the same kind you want to buy: jeans for jeans, dress trousers for dress trousers.
2. Lay them on a hard, smooth surface. Proper Cloth, in How To Measure Your Dress Pant: Inseam Length, lays the trousers on their side with the creases on top of each other, then lifts the top leg out of the way.
3. Smooth the bottom leg flat with a light spreading motion, without stretching it.
4. Hold the tape where the four seams meet at the crotch and run it down the inside leg seam to the bottom of the hem.
5. Read it to the nearest quarter inch (half a centimeter).

On washed jeans, the inside seam can twist around the leg. Maurice Malone of Williamsburg Garment Company, in How to Measure the Inseam on Jeans, says to follow the shape of the leg, where the seam should be, not the seam itself as it wanders.

Method 2: Measure on your body with a book (alone)

1. Take off your shoes and stand with your back against a wall, feet about 15 cm (6 inches) apart, in underwear or thin close-fitting trousers.
2. Hold a hardcover book flat between your legs, spine up, and raise it until it sits snugly at the top of your inner thighs, where the crotch of a well-fitting pair would sit. Keep it level.
3. Mark the wall at the top of the spine with a pencil.
4. Step away and measure from the floor to the mark. Do it twice.

This gives your leg length to the floor, barefoot. It is not the inseam you buy: trousers end above the floor and their crotch hangs a little below yours. Use it as a starting point, then check it against a pair you own or the brand's chart.

Method 3: With a helper

Put on the shoes you will wear and a pair of trousers close to the length you want. Stand straight with your weight even on both feet, and have the helper hold the tape at the crotch seam and run it down the inside of the leg to where you want the hem to land. Twillory, in How To Measure Inseam for Men's Pants, recommends this over trying it yourself, because bending over to hold the tape throws the number off.

Which method to use

If you own a pair whose length you like, use method 1 and nothing else. If you do not, use method 2 to get into the right range and buy one length longer, since length is easy to take up and hard to add. Use method 3 when you are having trousers hemmed or buying made-to-measure, where a centimeter matters.

How shoes and break change your inseam

Break is the fold the fabric makes where the hem rests on the shoe. Proper Cloth's guide to pant break describes four lengths: showing ankle (the hem stops above the shoe), no break (it just touches), half break (a soft fold at the front, no sock showing) and full break (the back reaches at least midway down the back of the shoe).

Three things follow:

• Measure in the shoes you will wear. Marks & Spencer's size guide defines inside leg as "from the crotch to where your trouser is normally worn on the shoe." A chunky boot and a thin-soled loafer need different hems on the same legs.
• The slimmer the leg, the shorter the hem. Justin Kwan explains in Trouser Length Explained that a narrow hem cannot sit around a shoe, so a full break on slim trousers collapses into bunches. Slim and tapered legs suit no break or a slight one. Wider legs can take more.
• Too long is fixable, too short is not. Most ready-made trousers can be hemmed. Letting them down depends on how much fabric is folded inside, which is often little. When in doubt, buy longer and see what a tailor can fix.

Worked example

Say you are 178 cm (5 feet 10). The book method gives 84 cm (33 inches) to the floor. Your favourite chinos measure 79 cm (31 inches) flat and sit with a slight break on sneakers. Ignore the 84: buy 31 in a brand that sells odd lengths, or 32 and have 2.5 cm (1 inch) taken up. For a slimmer pair you want to end with no break, go to 30 or hem the 32 to about 77 cm. For more on fit through the leg, see how dress pants should fit.

Typical inseam by height

Height is a rough guide, because two people of the same height can have very different leg lengths. These are the numbers brands publish. Notice that they do not agree.

Men

Source: Levi's size guide. Marks & Spencer sells its trousers in odd lengths instead: short 29 in (74 cm), regular 31 in (79 cm), long 33 in (84 cm) and extra long 35 in (89 cm).

Women

Sources: Levi's US size guide and UK size chart for the tall row, and NYDJ's inseam guide. At 5'5", Levi's points you to a 32 and NYDJ to 30 to 32. Lands' End draws its petite line at 5'3" and its tall line at 5'8", one inch lower than NYDJ. If your measured inseam and the chart disagree, trust the measurement.

Why the same inseam fits differently between brands

• Where the crotch point sits. Brands draft the crotch curve differently. A deeper rise puts the crotch lower on your body, so the same 30 inch leg ends lower on the shoe.
• Jeans and dress trousers are sold differently. Jeans come hemmed in fixed lengths, usually in 2 inch steps. Dress and suit trousers are often sold unfinished or with extra fabric inside the hem, so the label is a maximum, not the finished length.
• Shrinkage. Raw and shrink-to-fit denim loses length in the wash. Levi's tells buyers of its shrink-to-fit 501 who plan to machine wash and dry them to add 3 inches to the inseam for lengths 27 to 34, and 4 inches from 36 up.
• Factory tolerance. Two pairs with the same label can differ by about a centimeter. Compare the listing's garment chart with a pair you own; how to measure yourself shows how.

How to measure inseam for women

The method is the same. Three things differ in practice.

• Heels. Measure in the shoes you will wear most with that pair. Wide-leg and flared trousers are usually worn long, close to the floor, so a pair hemmed for heels will drag in flats. Hem for one height and keep the pair for those shoes.
• Cropped and ankle styles are meant to end above the ankle. NYDJ gives cropped inseams of about 24 to 26 inches for petite, 26 to 28 for regular and 28 to 30 for tall.
• Petite and tall are a different cut, not only a different length. The knee and rise move too, so a regular pair hemmed short can still sit wrong at the knee. See how jeans should fit for women.

Inseam on shorts

The inseam on shorts is measured exactly like trousers: crotch seam to hem along the inside of the leg. Where a given length lands depends on your thigh length. American Eagle's shorts inseam guide describes the common men's lengths:

If you are shorter, each length lands lower, so a 9 inch can reach past the knee. To choose, measure a pair of shorts you like. Women's shorts are measured the same way.

Cycling inseam is a different measurement

Bike shops mean something else by inseam. A cycling inseam is measured barefoot from the floor to the crotch, with the book pressed up firmly to copy the pressure of a saddle. Rouvy's guide warns against reading it off your jeans. The number is longer than your trouser inseam, so do not use one for the other.

FAQ

Is inseam the same as length on jeans? Yes. In a size like 32 x 30, the first number is the waist and the second is the inseam, both in inches.

Should my inseam measurement go to the floor? Not for trousers. Measure to where you want the hem to sit on your shoe. A to-the-floor body measurement is useful for bikes and as a starting point, but it is longer than the inseam you buy.

How do I measure inseam without a tape measure? Use a piece of string or a phone charger cable from the crotch seam to the hem, mark it with your fingers, and lay it along a ruler or a metal tape.

Is a 30 inch inseam short? It depends on height. Levi's lists a 30 for men of 5'6" to 5'8" and for women of 5'2" to 5'3", so it is a short length on a tall person and a regular one on many others.